Tripower problems and fire!
 

Hi guys, question, as I read more on Facebook, the more I have thoughts of not returning my tripower back to mr 66, it was born with it and also had a fire in the the mid seventies, I tracked all three owners before me, it was saved by a fire extinguisher, back then and put on the shelf, I had it completely rebuilt, but the problems still seem to have existed through the years for these set ups, I’ve seen the floats stick, the rear carbs overflowing and leaking out, the list is long on some of the sites of Facebook and the fires that are posted lately with all kinds of classics is scary, my guess on a lot is the old electrical systems...any thoughts or information to who to contact for a check up and or re -rebuilding Of the carbs? I know Mike From the tripower team is highly regarded, I carry a fire extinguisher at all times with the problems that can arise with our cars, but would love to bolt that set up back on, thoughts guys? Also I’m in southern NH or the Boston area, is there anyone in the area that specializes in these great set ups? Thanks Mike

With a fuel pressure regulator set at 3.5psi, properly set float, quality needle and seat, there should be no particular fire hazard compared to other carbs.

When it is said that tri-powers pose a special fire hazard, what they are really saying is that they are more prone to fuel leaks. There is some logic in that there are more fuel fittings, so more potential leak points, but I am not overly concerned.

I think the problem comes down to not using the outer carburetors - if you don't kick them in often enough they can get gummed up, particularly with today's gasoline.

Dick Boneske here on the board rebuilds them: http://forums.maxperformanceinc.com/...d.php?t=786342

Stock A/C Delco,

I have used TP on my cars on and off for over 50 years and have not found them more trouble prone than any other type carb. Everything from my 287 1955 Chieftain to a 455 powered 1963 Chevy PU. In fact the worst carb that I found over the years for flooding and leaking is the popular dual feed Holley. As for rebuilding your carbs if you don't want them recoated there is no reason that if you are careful you can't do them yourself. Follow all the instructions and measure carefully. If you run into a problem ask for help and you should be all set. It's not brain surgery. Just make sure everything is CLEAN. If you have a compressor blow out every passage with a blow gun. If not buy a can of compressed air like the computer guys use. Good luck.

Thanks guys , as in any case , carbs have their problems , I think I may plan a weekend and bolt it all in , run it and watch close to see what leaks and ask more questions, I have no experience with tripower , only 4bbl, so the set up is key as well, nice to see it on the shelf , but it’s sat long enough!, mike

I've had the same experience, but only for the past 41 years. The tripowers I have run were as reliable as any 4 barrel carb. The current, original born-with tripower on my '65 GTO has been there for 55 years and still works fine. I kitted the carbs about 25 years ago and while grungy looking, they work flawlessly.

except for jetting and needle and seats you only have to deal with the center carb if all are real pontiac tripower carbs.The end carbs are just dump carbs.If the throttle blades seat properly there should be no fuel pulled through them.Tom

Carbs
 

Thanks guys, carbs are all original #’s carbs , the set up survived the fire with the air cleaners taking the hit, the owner was smart, back then, to have a fire extinguisher on hand , he raced it it back in the day and had a repair kit always with him, sounds familiar? Lol, ...but the rebuild required all internals as would be expected, what I’m afraid of is just that , the needles, seats and proper settings of the floats, even the jet sizes I question,..... the company that rebuilt them was very reputable, but not a gto guys, there is one place in Pelham NH I’m considering ,Hobbs carburetors, been around a long time with good reputation, I’m thinking to bring the specs on the jet sizes and tell him my situation, hope he doesn’t get insulted with the jet spec sheet! , the more I look at it, and read the input from all of you, I think it’s worth a shot, mike

Dick Boneski on this site or Mike Wassen of Jon Havens IMO!Tom

Yes Hobbs has been around for a long time but has the guy that actually works on your carbs been around a long time? There is nothing he can do that you can't do. All measurements should come in the kit. If your engine is stock then your stock jets should be just fine. If your engine is not stock then Hobbs can't help you anyways.

It was north ave carb in Derry NH, out of business, good guys, Bob and his father in law, ......the carbs are one piece Of the hobby I never had luck with, always sent them out after a few attempts, motor is stock, I would rather let the guys like yourself, that know what they are doing, fix it, .......do what you know best and pay for the rest, holds true, Looking at everyday and coming up with a plan,

I have had many tri-power cars over the last 45 years and enjoyed them all. Are they more likely to catch fire than a single carburetor? Yes, for the reasons mentioned in the thread. IMO, they are three times as likely to catch fire as one carburetor. Doesn't mean they will ever catch fire though. No reason for them to. They have allot of fittings to check for leaks, no big deal. They have 3 floats that can stick and overflow, but still very, very little chance that will happen. Make sure your plug wires are in excellent shape and routed properly as that is generally the ignition source for a fire, especially around the rear carb. It so happens that the most likely time for a fuel leak and potential fire is when you first start one up. This is the most likely time a needle and float will stick because it's dry and the bowls are empty. I recommend pre-filling the carburetors for the first start up with a tiny funnel through the bowl vents. Just a few ounces in each bowl will get the floats, floating. If you don't want to do this, crank the engine for 10 seconds then stop. wait 15 seconds. Then crank 5 seconds. Wait 15 seconds. continue til it starts. This fills the bowls slowly and you can find leaks or issues before it floods badly. Nothing to be afraid of. Also nothing sounds better than a tri-power at full throttle all six throats singing that Pontiac song! Enjoy.

Tripower
 

Thanks for the encouragement and tips !, it’s a shame to have it sit, so it’s in the plans, the fittings are the key , looking st the rear carb, I can see the fuel fitting is just about bottomed out to the casting, that may need attention or replacement of the top section , everything else looks , it appeared to be the rear carb that it started from, keep you guys posted as it comes back together!

Some of these Tri-Power Carbs, over the years, have seen a lot of abuse and installation of the wrong parts and then get blamed when the issue was operator error.

I have had a Tri-Power set-up on the 64 from Day 1 with a short break during the college days where I installed a Factory 1964 4 bbl intake and matching AFB carb for some College Engineering Fuel Economy testing.

Neither carb system ever gave me an issue as far as functioning properly.
The only issue I ever had was because of a improper picture in a Pontiac Advertisement that showed the Tube and Plunger assy installed backward on a 1966 421 engine picture. This is the mechanical linkage set-up for 1964.

I changed my linkage and had a issue with the plunger getting hung up on the intake manifold cross-over when it came out of the tube. I have posted about this in the past.

I have seen repop fuel pumps that showed 9 psi on a fuel gage,
I have seen leaking fittings and poorly made steel fuel lines for the carbs cause issues.
I have seen float settings that were done incorrectly and caused high fuel levels in the bowls. And then there are the mismatched carb gaskets. 99% of the time human error.

The carbs unless butchered rarely are the reason for a fire issue.

Tom V.

Thanks Tom, looking at the fuel lines and the top section of rear carb, I believe I found at least one issue, any recommendations on fuel pumps ? This A/C delco fuel pump must be 10+ years old and will be replaced at the same time of installation , decided to bring the carbs to a reputable shop and just check the floats etc. so far , so good, finding out things I didn’t know ! Thanks guys